Physics202Midterm1ExamFall2008(M.Becker)Name(printed).Name(signatureasonID).Midterm1ExamLabSection_________Chapts.1719inYoung&Geller8eMultiplechoicequestions.Circlethecorrectanswer.Noworkneedbeshownandnopartialcreditwillbegiven.(5pts)1.Twoequallychargedspheresofmass1.Ogareplaced2.0cmapart.Whenreleased,theybegintoaccelerateat643m/s2.Whatisthemagnitudeofthechargeoneachsphere?(a)170nN(b)l4OnN(c)l2OnN(d)94nC(5pts)2.Averysmallballcontainingacharge—Qhangsfromalightstringbetweentwoverticalplates,asshowninthefigure.Whenreleasedfromresttheballwill(a)swingtotheright(b)swingtotheleft(c)remainhangingvertically(d)needmoreinformation14.J1IfIj.(5pts)3.WhenacertaincapacitorcarrieschargeofmagnitudeQoneachplate,itstoresenergyU.Inorderto storetwiceasmuchenergy,howmuchchargeshouldtherebeonitsplates?(a)/Q(b)2Q(c)4Q(d)8Q/H(5pts)4.Aprotonwitha speedof5.0x105m/sfallsthroughapotentialdifferenceVandtherebyincreasesitsspeedto8.0x105m/s.Throughwhatpotentialdifferencedidtheprotonfall?(a)2000V(b)1300V(c)3300V(c)4600V(e)660V(5pts)5.Twometalrodsareweldedtogetherendtoend.IfeachrodhasalengthLandaresistivityp,theresistivityofthecombinationwillbe(a)4p(b)2p(c)p(d)p/2(5pts)6.WhatisthecurrentthroughR1inthecircuitshowninthefigurebelow?(a)1.00A(b)0.67A(c)0.0A(d)9.80AIg320VOnthefollowingproblemsshowallyourwork.Partialcreditwillbegivenifearned.(10pts)7.Inredesigningaparallel-platecapacitorwith circularplates,youtripleboththediameteroftheplatesandtheirseparation.IftheoriginalcapacitorhascapacitanceC0,whatisthecapacitanceoftheredesignedcapacitorintermsofC0?(10pts)8.Ifyoutriplethelengthofacableandatthesametimedoubleitsdiameter,whatwillbetheresistanceifitsoriginalresistancewasR?(20pts)9.Twolargemetalplatescarryoppositechargesofequalmagnitude.Theyareseparatedby45.0mmandthepotentialdifferencebetweenthemis360V.(a)Whatisthemagnitudeoftheuniformelectricfieldintheregionbetweentheplates?(lopts)(b)Whatisthemagnitudeoftheforcethisfieldexertsonaparticleofcharge+2.4OnC?(lopts)(30pts)10.Twopointchargesareseparatedby